Adjustable mounting column



FIG. 1 is a front elevation view of an adjustable mounting column;

FIG. 2 is a rear elevation view of the adjustable mounting column depicted in FIG. 1;

FIG. 3 is a left end view thereof; and,

FIG. 4 is a right end view thereof.

The broken line depiction of the mounting structure is included for the purpose of illustrating environment and forms no part of the claimed design. 

The ornamental design for an adjustable mounting column, as shown and described. 